Ziegler olefin polymerisation catalyst - contains solid obtd. by drying silica or silica-alumina support dispersion in alcoholic vanadium tri:halide soln.

摘要

Ziegler catalyst system for the (co)polymerisation of 2-6C alpha-monolefins at 30-200 degrees C and 0.1-200 bar consists of (A) a component contg. V, (B) a metal cpd. of the formula MeAm-nXn (in which Me is Al, Mg or Zn. A is a 1-12C hydrocarbyl gp. X is Cl, Br or H. m is the valency of Me. n is 0 to m-1) and opt. (C) a 1-12C halohydrocarbon, the atomic ratio of V:Me being 1:0.1-400 and of (C);Me 1:0.1-60. The novelty is that (A) is the solid phase prod. obtd. by contacting a finely-divided, porous inorganic oxide (I) of the formula SiO2, aAl2O3 (in which a is 0-2) and a soln. of 1000 wt. pts. alcohol of the formula Z-OH (in which Z is a satd. 1-8C hyerocarbyl gp.) and 0.01-5 pts. V in the form of VX'3 (in which X is Cl and/or Br) in a (I):V wt. ratio of 1:0.01-0.2 to form a dispersion and evaporating the dispersion to dryness at a temp. below 200 degrees C and above the m.pt. of Z-OH. (I) has a particle dia. of 1-1000 um, pore vol. of 0.3-3 cm3/g and surface area of 100-1000 m2/g. The supported catalyst makes it possible to reduce the mol. wt. of the polymer relatively strongly, even with relatively small amts. of H2 as regulator, which is esp. important in the dry phase polymerisation process. Polymers with esp. favourable morphological properties can be obtd.